On Tue, Jul 24, 2012 at 01:52:32PM -0400, Jörn Engel wrote:
> On Tue, 24 July 2012 18:25:47 +0200, Borislav Petkov wrote:
> > > The advantage should be better robustness, in particular when dealing
> > > with cheap flash devices.
> >
> > In the sense that we flush the current sector after one second the
> > latest so that we can lose as small amount of data as possible if the
> > system crashes right at that point?
>
> In the sense that cheap devices don't always handle rewrites of the
> same sector well. Often this results in the entire erase block being
> rewritten, causing bad performance and wear-out. Many cheap devices
> aren't real block devices. They are barely good enough to support
> FAT and may die near-instantly with a different write pattern.
> Blockconsole assumes utter crap as an underlying device.
>
> The timer mainly ensures that, on a quiet system, those two lines of
> output from half an hour ago actually make it to the device
> eventually. In the case of a crash, the panic notifier is supposed to
> do the same for those messages you _really_ care about.
>
> > Ok, I see what you mean. I see a red line in vim here. Ok, good to know,
> > maybe this feature with the empty lines could be in the docs too so
> > people don't ask that question again?
>
> Last paragraph. ;)
>
> > Or you issue a tag instead of an empty line like so:
> >
> > [ 10.498422] console [bcon0] enabled
> > [ 10.499899] blockconsole: now logging to /dev/sdc at 1
> > [ 10.594791] usb 5-2: new full-speed USB device number 3 using ohci_hcd
> > <<LOG timeout of 1sec>>
> > [ 12.665911] xhci_hcd 0000:00:10.0: xHCI Host Controller
> > [ 12.668469] xhci_hcd 0000:00:10.0: new USB bus registered, assigned bus
> > number 6
> >
> > which explains everything.
>
> That would only work if you have at least 26 bytes to pad. Bunch of
> spaces with a newline works for any value between 0 and 512.
Ok, thanks for taking the time to explain this - very interesting stuff.
So, as far as I'm concerned blockconsole is ready for shipping! 8-)
--
Regards/Gruss,
Boris.
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